Looks cool but how much does it cost?

Probably gets pretty costly if you’re running a lot of data through it. Now if you could implement a Tailscale DERP server in a lambda that would be pretty amazing: https://tailscale.com/kb/1232/derp-servers

Very interesting concept. I’d love some cheap and “throw away” method of setting up tunnels with minimal onus on the exit nodes.

Alternatively, you could make a Nix flake that can generate an immutable microVM image based on Solo5, running a MirageOS unikernel that implements NAT traversal with UDP hole punching and relay fallback. This image can be deployed to Fly.io as a lightweight, autoscaling Firecracker VM with per-second billing. It boots in milliseconds and costs far less than Lambda.

Any reason to use lambda vs this cloud-agnostic approach? Maybe I am missing something. I guess per second vs per 100ms billing, but I can't imagine it ends up being cheaper with Lambda.